Wood treated with a preservative composition

ABSTRACT

WOOD TREATED WITH A PRESERVATIVE COMPOSITION COMPRISED OF CREOSOTE IN WHICH IS DISSOLVED THE NOVEL ARSENICCONTAINING COMPOUND 1 - (BIS(2 - HYDROXYPROPYL) NITRILOETHYLENE) - 5 - ARSA - 1 - AZA - 4,6 - DIOXACYCLOOCTYL ASETHER WHOSE STRUCTURE IS   O(-AS&lt;(-O-CH(-CH3)-CH2-N(-(CH2)2-N(-CH2-CH(-CH3)-OH)2)-   CH2-CH(-CH3)-O-))2

United WOOD TREATED WITH A PRESERVATIVE COMPOSITION Woodrow E. Kemp,Pittsburgh, Pa., assignor to Koppers Company, Inc. No Drawing. FiledJan. 26, 1972, Ser. No. 221,080 Int. Cl. B27c 3/50; C07d 105/06 US. Cl.117147 1 Claim ABSTRACT OF THE DISCLOSURE Wood treated with apreservative composition comprised of creosote in which is dissolved thenovel arseniccontaining compound 1 (bis(2 hydroxypropyl)nitriloethylene)5 arsa 1 aza 4,6 dioxacyclooctyl Asether whose structure is FIELD OF THEINVENTION This invention relates generally to a wood preservativecomposition, and in particular to an organic arsenic compound that issoluble in creosote to provide a preservative composition for thetreating of wood.

There has now been discovered a novel arsenic organic compound which issoluble in creosote and can be used for the fortification of thecreosote, i.e., for the enhancement of the toxic properties of thecreosote which is to be used for the impregnation of wood to preservethe wood.

BACKGROUND OF THE INVENTION Wood being a product of nature is attackedby natural organisms such as insects. A group of chemical compoundswhich finds widespread use, due to its toxic properties, as a woodpreservative, is creosote. Coal-tar creosote is not a single chemicalsubstance but is a mixture containing a great number of aromaticcompounds. Such creosote is a distillate of the coal-tar produced by thehigh temperature carbonization of coal. This distillate begins at about200 C. and has a continuous boiling range of at least 125 C. and iscomprised of liquid and solid aromatic hydrocarbons, containsappreciable quantities of tar acids and tar bases. When the creosote isimpregnated into wood, it renders the wood toxic to fungi and mostorganisms. Still, there are certain organisms which have a tolerance tocreosote and will attack lumber which has been treated with creosote.

Another group of compounds that have well-known toxic effects on livingorganisms are compounds involving arsenic. Some uses of arsenic and itscompounds depend upon the chemical and physical properties of arsenic,but the greatest use of arsenic and its compounds depend upon somefeature of the toxic properties. Arsenic compounds are poisonous toliving organisms and widespread use is made of this characteristic ofarsenic compounds in insecticides, fungicides, poisons, and weedkillers. Arsenic compounds, however, have peculiarities in solubilitycharacteristic and decomposition characteristic that limit its use manytimes.

In accordance with this invention, a novel arsenic compound has beenfound that is compatible with creosote. Now a wood preservative compoundcan be formed that includes the toxic qualities of arsenic compounds aswell as those of creosote.

atented Oct. 9, 1973 SUMMARY OF THE INVENTION This invention relatesgenerally to Wood preservative compositions and more particularly to asolution of l-(bis- 2 hydroxypropyl)nitriloethylene) 5 arsa 1 aza- 4,6dioxacyclooctyl As-ether in creosote. This novel organic arseniccompound has the general structure The novel organic arsenic compound isformed by the reaction of arsenous oxide (AS203) with N,N,N,N'-tetrakis(2-hydroxypropyl) ethylene diamine.

The N,N,N,N-tetrakis (2-hydroxypropyl) ethylene diamine is readilyavailable commercially as a viscous, water-white liquid. The arsenictrioxide is a white amorphous powder.

The novel organic arsenic compound is quite soluble in creosote. Inparts by weight, for example, 40 parts will dissolve in parts ofcreosote. The organic arsenic may either be formed separately and addedto the creosote or may be formed in situ in the creosote. Forming theorganic arsenic compound in situ is advantageous when the solution ofthe organic arsenic compound is to be used for the impregnation of woodbecause it then is not necessary to purify the resulting product. Thesolution of the organic arsenic compound in creosote, a fortifiedcreosote, may be used in the conventional manner as is used creosote forthe impregnation of wood.

The wood may be impregnated with a solution of the organic arseniccompound in creosote, the fortified creosote, by either the well-knownempty cell or full cell" method to obtain the desired retention of thepreservative in the Wood. As with creosote, the amount of preservative,fortified creosote, to be placed in the wood will vary with the use tobe made of the wood. For example, 4 to 5 pounds of fortified creosotewould be retained per cubic foot of wood when the wood is to be used,for ex-= ample, for fence posts. For lighting poles, railroad ties, andthe like, the retention, of course, increases to 5 to 12 pounds offortified creosote per cubic foot of wood. For marine use, of course,even greater retention is re-= quired, the retention being 20 to 25pounds of fortified creosote per cubic foot of wood.

The organic arsenic compound of this invention can, of course, be"-usedto the extent of forming a saturated solution in fortifying thecreosote. Normally, a 35% by weight of "organic arsenic compound in thecreosote solution is considered suflicient to provide the additionaltoxicity to preserve wood against attack by organisms that are tolerantto creosote.

DETAILED DESCRIPTION The invention will be illustrated more clearly bythe following examples.

Example I Two hundred sixty five grams of N,N,N,N'-tetrakis(2-hydroxypropyl)ethylene diamine is charged to a 1 liter stirred flaskequipped with a water trap. Fifty grams of xylene is added, the mixtureheated to C. and then 215 grams of arsenic trioxide is added over aperiod of 5 minutes. The mixture is refluxed for 1 /2 hours at 107 to123 C. and the water evolved from the compound formation is collected inthe trap (16.4 ml.). The viscous product mixture is cooled to roomtemperature and this new composition of matter is purified by acetoneextrac= tion. The purified compound is pale tan colored solid melting at52 to 54 C.

3 Based on a molecular weight of 746, an elemental arsenic content of20.2 (theory 20.1), an As-O band at 15.9 microns, and NMR analysis, thestructural formula of the compound is:

The solubility if the compound is creosote is 40 grams of compound per100 grams of creosote.

Example II To 10,000 grams of creosote was added 265 grams ofN,N,N',N'-tetrakis (Z-hydroxypropyl)ethylene 'diamine. The mixture isplaced in a stir reactor and heated to 125 C., then 215 grams of arsenictrioxide is added over a period of 5 minutes. The mixture is heated to125 C. and kept under a-gitation for a period of 2 hours. The arsenictrioxide solid disappears as the reaction proceeds to form the novelcompound. 1 (bis(2 hydroxypropyl) nitriloethylene) 5 arsa 1 aza 4,6dioxacyclooctyl As-ether in situ.

The advantage of this in situ preparation is that the fortified creosoteis produced without further treatment.

The N,N,N,N' tetrakis (2 hydroxypropyl)ethylene di- 3 amine is solublein the creosote, but the arsenic trioxide is not. However, disappearanceof the solids as the reaction proceeds permits the operation todetermine completion of the organic reaction as the arsenic compound ofthe invention is formed.

The foregoing has described a novel organic arsenic compound which canbe used for the fortification of creosote for the preservation oflumber. The fortified creosote can be formed by the organic arseniccompound either being synthesized and then added to the creosote, or thecompound being made in situ in a creosote medium. The novel fortifiedcreosote can be used in conventional equipment for the impregnation oflumber.

What is claimed is:

1. Wood treated with a preservative composition comprising creosote anda compound having the structure Gin on. ire-$11411. CH2 1-1-0 1 NOH-CHQN As Ho-oH-CI-n CHZ-CHO/ J Ha H3 2 References Cited UNITED STATESPATENTS 3,109,853 11/1963 Worsley et al. 260-440 3,158,637 11/1964 Markset a1. 260440 3,299,173 1/1967 Roselli 260440 WILLIAM D. MARTIN, PrimaryExaminer W. R. TRENOR, Assistant Examiner US. Cl. X.R..

21-7; 10615 FP; 1l7-151;260440;424297, 339, 346

